1. Field of the Invention
The present invention relates generally to rotary machines and more particularly, to a construction for use in pumps, compressors and motors with an axially moving partition.
2. Prior Art
Rotary machine constructions are known whose operation or use is as pumps, compressors or motors with a fluid, liquid or gaseous medium.
Rotary machines are known that make use of movable radial partitions between a rotor and a stator. These partitions are installed in radial grooves of the rotor and rotate therewith. Such rotor machines are generally referred to as "vane rotary machines" and possess a high degree of variation of volume of working space filled with the fluid medium as compared to other rotary machines.
In the vane rotary machines, the working space is formed between the internal cylindrical surface of a stator and the rotor surface and varies radially around the rotor. Since there are pressure differentials in the working space, a reliable seal must be effected on the periphery of the partitions to avoid leakage therebetween. However, sealing this type of partition is a very complex problem since the partitions rotate together with the rotor and are influenced by rotor torque. Moreover, their edges interact with the internal cylindrical surface of the stator and with flat end face surfaces of the stator.
If a circumferential seal of the vane partitions is not properly provided, the efficiency of the rotary machine is reduced because of leakage of fluid between the working spaces formed by the vanes thereof. The necessity of providing a proper circumferential seal in the vane rotary machines renders this kind of rotor machine complex in the construction and manufacture thereof.
There is known in the prior art a compressor made as a rotary machine wherein a partition dividing the working space into isolated chambers does not take part in the rotary motion together with the rotor. This machine comprises a cylindrical housing accommodating a shaft arranged along the axis of the housing and having a rotor fixed thereto whose circumferential surfaces are in sliding contact with the internal cylindrical surface of the housing along the entire length. The radially extending surface of the rotor is shaped so that it is in sliding contact with the stationary wall arranged normal to the shaft axis forming together therewith a working space with dimensions variable radially and axially. The space is divided into chambers communicating with inlet and outlet ports and isolated from each other by a partition arranged along the shaft axis and movable in this direction. The partition passes through a radially extending slot in the stationary wall and interacts with a radially extending shaped surface of the rotor. Such an apparatus is described in FRG Pat. No. 2,641,451 patented on March 16, 1978. This known rotary machine is the closest prior art to the rotary machine of the present invention.